Coating for screens and the like



Patented July 27, 19.26.

UNITED sra'rns HENRY E. .IO DOIN, OF INDIAN ORCHARD,- MASSACIIUS ETTS.

COATING FOR SCREENS AND THE LIKE.

No Drawing.

In the projection of photographic pic tures "and particularly in the so-called moving picture the screen or surface of display has presented a problem of considerable difficulty.

This problem is variously complicated by the material of the receiving surface and by its treatment. Taking for example the usual dropin such we have a fabric usually rolled and unrolled with considerable frequency and subjected to the widest variety of use and abuse.

lVhen it is considered that the physical intercept of a figured beam of light involves an infinitely varied problem of absorption and reflection, it is readily appreciated that the character of the surface is one of supreme importance. The usual picture as displayed is uncolored but I have discovered that even in such the factor of color must be taken into account. In the case of colored displays the screen factor is of even more importance. For the sake of simplicity, however, I will discuss my invention in connection with the uncolored picture or at least as it is generally so considered.

All sources of projection illumination emit light more or less colored. Furthermore, films or other photographic pictures are taken from objects or surroundings variously colored. My invention therefore contemplates the introduction of color factors in the screen surface asa means of reproducing the various qualities of the picture inherently present but heretofore undeveloped.

Reverting directly to the substance of my invention, I have selected as illustrative thereof a specific application which is direct and applicable and yet serves to show to those skilled in the art those principles upon which my invention is founded.

By the way of example, I will take the problem of surface coating an ordinary screen or drop of textile character. These are particularly susceptible to moisture which is another problem of the commercial moving picture house. Here is a continuously gathering constantly changing audience constantly admitting and introducing new factors of moisture and vapors which generally trend toward the proscenium arch or the screen plane. This introduces a factor of disintegration or at least of tarnish on the screen. Briefly also there Application filed May 15, 1924.

Serial No. 713,618.

is the factor of fire risk. Obviously the screen is a hazardor an element of safety.

I will therefore proceed to discuss my invention in the light of such suggested conditions. In accordance with my invention I am able to treat any screen or drop in any ordinary state of repair or passable condition and bring it to relative perfection as follows:

I utilize a coating which may be variously prepared but for simplicity and directness I disclose it in what seems to me its most direct and usable form.

For general use on any reasonably intact surface I prepare a coating for which the following affords direction.

I prepare a coating for which in a small amount I utilize a calcareous base, as for example, five pounds of calcimine. Almostany white mineral base will do, but I prefer to use one which is of a chalky character. This I wet up and work to a pasty consistency. I take a solution of ammonium dichromate (one-half ounce dissolved in cold water to give a fine solution) and stir this into the calcimine cream adding about four quarts of water to bring the whole to a water thin paint consistency adapted to be applied as a paint or coating to the screen. This introduces a binding and a Waterproofing factor and gives to the mixture a setting texture that is very highly desirable. One important effect of such a coating lies in its fireproofing or fire retarding eflect.

The coating is so resistant that if applied 9 even to paper it may be exposed to flame. My coating, therefore, affords for any surface a very considerable flame resistance which in the case of ordinary drops is a most important factor.

In addition to these factors as will be discussed later, I introduce glycerine into the mixture. As explained the usual screen or drop problem is a hard one regarded mechanically. By providing for a maximum of flexibility in my coating I make the treated surface so flexible that it is capable of withstanding extremely rough usa es. Moreover, my coating made as indicate is capable of adaptation to, or the filling of defects and blemishes in the screen surface so that they are imperceivable in the icture as projected. These relate to the physical make up of the coating but there remains the important chromatic factor.

obviously vary in color and. intensity but for,

sake of simplicity I refer to Well known standard commercial. dyes, i. e. take such. commercial!dyes.as Diamond dyes, Of these I take of the blue onecommercial package placing itin one of; the flasks and agitating.

I take one package of the, Turkey red and shake into another flask, and similarly introduce one packageof the green in the third. The uncorked flasks, shouldthen beheated; in hot water standing for one-halt hour. They. can then be; corked. and allowed to stand, for thirty-six hours more.

The resultant glycerine solutions will be clear and complete and in. condition for subsequent use. To the mix from; the original live pound, batch I add of thegreen solution five drops; of the blue solutiontwenty drops and of the Turkey red. solution one-half ounce. These are added -withi stirrings maintaining the same direction,

I add these by consistent stirrings in the same direetion until entirely blended butas blue factor. of thepicture and at the same.

time correlates the so-called white of the calcimine, The green. is responsivetothe,green rays of; the source of projection whilethe red. 1

is directly responsixze tov the general I'QIlICQIlr ditions of photographic reproductlon.

Various modifications may be resortedto.

inv composition, colorqrelation and other oronerties, such. as water aroofin and all;-

without. passing the bounds of my inventionz.

What I therefore claim and ClBSlI'L-l'tOjSfi: cure by Letterslatent is:

A coating for pictmrescreensand;the.like comprising finely divided White.- calcareous base, an ammonium dichromate dissolved therein, and plural elementary dyes-.intrmv duced: therein in amountsv .lnsufiiclent to. visibly change the apparentwhiteness, but.

responsive to color in a projected beam.

In testimony whereof I hayehereunto. at.

fixedv my signature.

HENRY E..JODOI'N. 

